The Origin of the Genus Homo

Summary

The earliest members of our own genus evolved from an austral- pithecine species in Africa. The spread of hominids out of Africa probably occurred about 1.5 million years ago, but by then our ancestors had already attained many features considered to be uniquely human. Several species of australopithecine are well known from African deposits about 4-1 million years old. They had marked sexual dimorphism in body size (like that of gorillas), were upright bipeds, had small canine teeth, and relatively small brains. There are indications that they retained some arboreal behaviors despite being erect bipeds. The first good evidence of early Homo shows us that the first members of the species H. erectus were very like our own species in many respects. They were large people with sexual dimorphism in body size to match that of modern human populations, relatively large brains, and had modern limb proportions that show physiological adaptations according to Allen’s rule. They show a few primitive characteristics as well as hint at mosaic evolution in our species. The intermediate species between Australopithecus and Homo, H. habilis is poorly-known and emphasis should be placed on recovering more fossils from the critical 2.5–2.0 Ma period.

Stringer CB (1984) The definition of Homo erectus and the existence of the species in Africa and Europe. In: Andrews P, Franzen JL (eds) The early evolution of man. Courier Forschungsinstitut Senckenberg, Frankfurt, pp 131–143Google Scholar